1. Field of the Invention
The present invention relates to an image processing apparatus and a print control apparatus.
2. Description of the Prior Art
In recent years, image input devices such as digital cameras are spreading rapidly, and image data produced by image input devices are more and more used. This image data is, for example, data that represent the gradation of colors for each color component of three colors, RGB (red, green, and blue), and can be readily processed. This allows automatic image quality adjustment when utilizing image data, as in printing (refer to Japanese Patent Laid-open No. 2002-314809, for example).
With the prior arts, it was difficult to automatically improve mage quality to an appropriate level, for an image whose image quality could not be appropriately improved during the process of producing image data in the image input device. For example, it was difficult to appropriately perform an exposure correction to compensate for excessive or deficient exposure in producing image data, and color balance correction, such as white balance adjustment, to correct unbalanced colors. Particularly, it was impossible to achieve desired correction only by constant multiplication of the amount of light to correct inappropriate color balance or exposure, or constant multiplication of the gradation value for each color, which made it difficult to perform appropriate correction automatically or manually. Furthermore, although nonlinear correction such as the γ correction can be performed as well as multiplying the gradation value, it was difficult to automatically or manually determine an appropriate nonlinear characteristic even in the nonlinear correction.